Bug 1125 - Make ELF Reader 'jogamp.common.os.elf' Stateless

ELF Reader 'jogamp.common.os.elf' currently uses
Platform's pre-determined OS_TYPE and CPUType.

It also uses the host platforms MachineDescription,
hence can not read ELF files from other machines.

This also forbids Platform to determine CPUType etc
w/o having a valid 'os.arch' property.

+++

ElfHeader should be split in
  - ElfHeaderPart1 (CPUType independent)
  - ElfHeaderPart2 (CPUType dependent)

Fix shall make the ELF Reader self containing
by only using ELF CPUType data, etc.

This requires customization of struct parsing,
where MachineDescription.Static index shall be
  - defined in ElfHeaderPart1 using e_Ident's CPUType.
  - used in ElfHeaderPart2 and all its struct types.

6 files changed, 248 insertions, 156 deletions

diff --git a/src/java/com/jogamp/common/os/AndroidVersion.java b/src/java/com/jogamp/common/os/AndroidVersion.java
index f727a47..840933f 100644
--- a/src/java/com/jogamp/common/os/AndroidVersion.java
+++ b/src/java/com/jogamp/common/os/AndroidVersion.java
@@ -30,7 +30,6 @@ package com.jogamp.common.os;
 import java.lang.reflect.Field;
 
 import com.jogamp.common.os.Platform.ABIType;
-import com.jogamp.common.os.Platform.CPUFamily;
 import com.jogamp.common.os.Platform.CPUType;
 import com.jogamp.common.util.IntObjectHashMap;
 import com.jogamp.common.util.ReflectionUtil;
@@ -67,61 +66,6 @@ public class AndroidVersion {
     private static final String androidBuildVersion = "android.os.Build$VERSION";
     private static final String androidBuildVersionCodes = "android.os.Build$VERSION_CODES";
 
-    /**
-     * Returns {@link CPUType} for matching <code>cpuABI<code>,
-     * i.e. {@link #CPU_ABI} or {@link #CPU_ABI2},
-     * or <code>null</code> for no match.
-     * <p>
-     * FIXME: Where is a comprehensive list of known 'android.os.Build.CPU_ABI' and 'android.os.Build.CPU_ABI2' strings ?<br/>
-     * Fount this one: <code>http://www.kandroid.org/ndk/docs/CPU-ARCH-ABIS.html</code>
-     * <pre>
-     *  lib/armeabi/libfoo.so
-     *  lib/armeabi-v7a/libfoo.so
-     *  lib/x86/libfoo.so
-     *  lib/mips/libfoo.so
-     * </pre>
-     * </p>
-     */
-    private static final CPUType getCPUTypeImpl(final String cpuABI) {
-        if( null == cpuABI ) {
-            return null;
-        } else if( cpuABI.equals("armv8-a")   ||
-                   cpuABI.equals("arm64-v8a") ) {
-            return CPUType.ARMv8_A;
-        } else if( cpuABI.equals("aarch64")   ||
-                   cpuABI.startsWith("arm64") ) {
-            return CPUType.ARM64;
-        } else if( cpuABI.equals("armeabi-v7a") ||
-                   cpuABI.equals("armeabi-v7a-hard") ) {
-            return CPUType.ARMv7;
-        } else if( cpuABI.equals("armeabi") ||
-                   cpuABI.startsWith("arm") ) { // last 32bit chance ..
-            return CPUType.ARM;
-        } else if( cpuABI.equals("x86") ) {
-            return CPUType.X86_32;
-        } else if( cpuABI.equals("mips") ) {    // no 32bit vs 64bit identifier ?
-            return CPUType.MIPS_32;
-        } else {
-            return null;
-        }
-    }
-    private static final ABIType getABITypeImpl(final CPUType cpuType, final String cpuABI) {
-        if( null == cpuType || null == cpuABI ) {
-            return null;
-        } else if( CPUFamily.ARM == cpuType.family ) {
-            if( CPUType.ARM64   == cpuType ||
-                       CPUType.ARMv8_A == cpuType ) {
-                return ABIType.EABI_AARCH64;
-            } else if( cpuABI.equals("armeabi-v7a-hard") ) {
-                return ABIType.EABI_GNU_ARMHF;
-            } else {
-                return ABIType.EABI_GNU_ARMEL;
-            }
-        } else {
-            return ABIType.GENERIC_ABI;
-        }
-    }
-
     static {
         final ClassLoader cl = AndroidVersion.class.getClassLoader();
         Class<?> abClass = null;
@@ -138,7 +82,7 @@ public class AndroidVersion {
             abvcClass = ReflectionUtil.getClass(androidBuildVersionCodes, true, cl);
             abvcObject = abvcClass.newInstance();
         } catch (final Exception e) { /* n/a */ }
-        isAvailable = null != abObject && null != abvObject && null != abvcObject;
+        isAvailable = null != abObject && null != abvObject;
         if(isAvailable) {
             CPU_ABI = getString(abClass, abObject, "CPU_ABI", true);
             CPU_ABI2 = getString(abClass, abObject, "CPU_ABI2", true);
@@ -146,9 +90,36 @@ public class AndroidVersion {
             INCREMENTAL = getString(abvClass, abvObject, "INCREMENTAL", false);
             RELEASE = getString(abvClass, abvObject, "RELEASE", false);
             SDK_INT = getInt(abvClass, abvObject, "SDK_INT");
-            final IntObjectHashMap version_codes = getVersionCodes(abvcClass, abvcObject);
-            final String sdk_name = (String) version_codes.get(SDK_INT);
+            final String sdk_name;
+            if( null != abvcObject ) {
+                final IntObjectHashMap version_codes = getVersionCodes(abvcClass, abvcObject);
+                sdk_name = (String) version_codes.get(SDK_INT);
+            } else {
+                sdk_name = null;
+            }
             SDK_NAME = ( null != sdk_name ) ? sdk_name : "SDK_"+SDK_INT ;
+
+            /**
+             * <p>
+             * FIXME: Where is a comprehensive list of known 'android.os.Build.CPU_ABI' and 'android.os.Build.CPU_ABI2' strings ?<br/>
+             * Fount this one: <code>http://www.kandroid.org/ndk/docs/CPU-ARCH-ABIS.html</code>
+             * <pre>
+             *  lib/armeabi/libfoo.so
+             *  lib/armeabi-v7a/libfoo.so
+             *  lib/x86/libfoo.so
+             *  lib/mips/libfoo.so
+             * </pre>
+             * </p>
+             */
+            CPU_TYPE = Platform.CPUType.query(CPU_ABI);
+            ABI_TYPE = Platform.ABIType.query(CPU_TYPE, CPU_ABI);
+            if( null != CPU_ABI2 && CPU_ABI2.length() > 0 ) {
+                CPU_TYPE2 = Platform.CPUType.query(CPU_ABI2);
+                ABI_TYPE2 = Platform.ABIType.query(CPU_TYPE2, CPU_ABI2);
+            } else {
+                CPU_TYPE2 = null;
+                ABI_TYPE2 = null;
+            }
         } else {
             CPU_ABI = null;
             CPU_ABI2 = null;
@@ -157,11 +128,11 @@ public class AndroidVersion {
             RELEASE = null;
             SDK_INT = -1;
             SDK_NAME = null;
+            CPU_TYPE = null;
+            ABI_TYPE = null;
+            CPU_TYPE2 = null;
+            ABI_TYPE2 = null;
         }
-        CPU_TYPE = getCPUTypeImpl(CPU_ABI);
-        ABI_TYPE = getABITypeImpl(CPU_TYPE, CPU_ABI);
-        CPU_TYPE2 = getCPUTypeImpl(CPU_ABI2);
-        ABI_TYPE2 = getABITypeImpl(CPU_TYPE2, CPU_ABI2);
     }
 
     private static final IntObjectHashMap getVersionCodes(final Class<?> cls, final Object obj) {
diff --git a/src/java/com/jogamp/common/os/MachineDescription.java b/src/java/com/jogamp/common/os/MachineDescription.java
index 98093d0..2a4627e 100644
--- a/src/java/com/jogamp/common/os/MachineDescription.java
+++ b/src/java/com/jogamp/common/os/MachineDescription.java
@@ -104,7 +104,7 @@ public class MachineDescription {
                                            alignments[j++]);
       }
 
-      public StringBuilder toString(StringBuilder sb) {
+      public final StringBuilder toString(StringBuilder sb) {
         if(null==sb) {
             sb = new StringBuilder();
         }
@@ -112,7 +112,9 @@ public class MachineDescription {
         md.toString(sb);
         return sb;
       }
-
+      public final String toShortString() {
+          return this.name()+"("+this.ordinal()+")";
+      }
       @Override
       public String toString() {
         return toString(null).toString();
diff --git a/src/java/com/jogamp/common/os/Platform.java b/src/java/com/jogamp/common/os/Platform.java
index 0d00a9a..6f6c99d 100644
--- a/src/java/com/jogamp/common/os/Platform.java
+++ b/src/java/com/jogamp/common/os/Platform.java
@@ -58,97 +58,186 @@ import jogamp.common.os.PlatformPropsImpl;
 public class Platform extends PlatformPropsImpl {
 
     public enum OSType {
-        LINUX(0), FREEBSD(1), ANDROID(2), MACOS(3), SUNOS(4), HPUX(5), WINDOWS(6), OPENKODE(7);
-
-        public final int id;
-
-        OSType(final int id){
-            this.id = id;
-        }
+        LINUX, FREEBSD, ANDROID, MACOS, SUNOS, HPUX, WINDOWS, OPENKODE;
     }
 
     public enum CPUFamily {
         /** AMD/Intel */
-        X86(    0x00000000),
+        X86,
         /** ARM */
-        ARM(    0x00010000),
+        ARM,
         /** Power PC */
-        PPC(    0x00020000),
+        PPC,
         /** SPARC */
-        SPARC(  0x00030000),
+        SPARC,
         /** Mips */
-        MIPS(   0x00040000),
+        MIPS,
         /** PA RISC */
-        PA_RISC(0xFFFF0000),
+        PA_RISC,
         /** Itanium */
-        IA64(   0xFFFF1000);
-
-        public final int id;
-
-        CPUFamily(final int id){
-            this.id = id;
-        }
+        IA64;
     }
 
     public enum CPUType {
         /** X86 32bit */
-        X86_32(    CPUFamily.X86,     0x0001, true),
+        X86_32(    CPUFamily.X86,     true),
         /** X86 64bit */
-        X86_64(    CPUFamily.X86,     0x0002, false),
+        X86_64(    CPUFamily.X86,     false),
         /** ARM 32bit default */
-        ARM(       CPUFamily.ARM,     0x0000, true),
+        ARM(       CPUFamily.ARM,     true),
         /** ARM7EJ, ARM9E, ARM10E, XScale */
-        ARMv5(     CPUFamily.ARM,     0x0001, true),
+        ARMv5(     CPUFamily.ARM,     true),
         /** ARM11 */
-        ARMv6(     CPUFamily.ARM,     0x0002, true),
+        ARMv6(     CPUFamily.ARM,     true),
         /** ARM Cortex */
-        ARMv7(     CPUFamily.ARM,     0x0004, true),
+        ARMv7(     CPUFamily.ARM,     true),
         /** ARM64 default (64bit) */
-        ARM64(     CPUFamily.ARM,     0x0008, false),
+        ARM64(     CPUFamily.ARM,     false),
         /** ARM AArch64 (64bit) */
-        ARMv8_A(   CPUFamily.ARM,     0x0010, false),
+        ARMv8_A(   CPUFamily.ARM,     false),
         /** PPC 32bit default */
-        PPC(       CPUFamily.PPC,     0x0000, true),
+        PPC(       CPUFamily.PPC,     true),
+        /** PPC 64bit default */
+        PPC64(     CPUFamily.PPC,     false),
         /** SPARC 32bit */
-        SPARC_32(  CPUFamily.SPARC,   0x0001, true),
+        SPARC_32(  CPUFamily.SPARC,   true),
         /** SPARC 64bit */
-        SPARCV9_64(CPUFamily.SPARC,   0x0002, false),
+        SPARCV9_64(CPUFamily.SPARC,   false),
         /** MIPS 32bit */
-        MIPS_32(  CPUFamily.MIPS,     0x0001, true),
+        MIPS_32(   CPUFamily.MIPS,    true),
         /** MIPS 64bit */
-        MIPS_64(  CPUFamily.MIPS,     0x0002, false),
+        MIPS_64(   CPUFamily.MIPS,    false),
         /** Itanium 64bit default */
-        IA64(      CPUFamily.IA64,    0x0000, false),
+        IA64(      CPUFamily.IA64,    false),
         /** PA_RISC2_0 64bit */
-        PA_RISC2_0(CPUFamily.PA_RISC, 0x0001, false);
+        PA_RISC2_0(CPUFamily.PA_RISC, false);
 
-        public final int id;
         public final CPUFamily family;
         public final boolean is32Bit;
 
-        CPUType(final CPUFamily type, final int id, final boolean is32Bit){
+        CPUType(final CPUFamily type, final boolean is32Bit){
             this.family = type;
-            this.id = id;
             this.is32Bit = is32Bit;
         }
 
-        public CPUFamily getFamily() { return family; }
+        /**
+         * Returns {@code true} if the given {@link CPUType} is compatible
+         * w/ this one, i.e. at least {@link #family} and {@link #is32Bit} is equal.
+         */
+        public final boolean isCompatible(final CPUType other) {
+            if( null == other ) {
+                return false;
+            } else if( other == this ) {
+                return true;
+            } else {
+                return this.family == other.family &&
+                       this.is32Bit == other.is32Bit;
+            }
+        }
+
+        public static final CPUType query(final String cpuABILower) {
+            if( null == cpuABILower ) {
+                throw new IllegalArgumentException("Null cpuABILower arg");
+            }
+            if(        cpuABILower.equals("x86")  ||
+                       cpuABILower.equals("i386") ||
+                       cpuABILower.equals("i486") ||
+                       cpuABILower.equals("i586") ||
+                       cpuABILower.equals("i686") ) {
+                return X86_32;
+            } else if( cpuABILower.equals("x86_64") ||
+                       cpuABILower.equals("amd64")  ) {
+                return X86_64;
+            } else if( cpuABILower.equals("ia64") ) {
+                return IA64;
+            } else if( cpuABILower.equals("aarch64") ) {
+                return ARM64;
+            } else if( cpuABILower.startsWith("arm") ) {
+                if(        cpuABILower.equals("armv8-a")   ||
+                           cpuABILower.equals("arm-v8-a") ||
+                           cpuABILower.equals("arm-8-a") ||
+                           cpuABILower.equals("arm64-v8a") ) {
+                    return ARMv8_A;
+                } else if( cpuABILower.startsWith("arm64") ) {
+                    return ARM64;
+                } else if( cpuABILower.startsWith("armv7") ||
+                           cpuABILower.startsWith("arm-v7") ||
+                           cpuABILower.startsWith("arm-7") ||
+                           cpuABILower.startsWith("armeabi-v7") ) {
+                    return ARMv7;
+                } else if( cpuABILower.startsWith("armv5") ||
+                           cpuABILower.startsWith("arm-v5") ||
+                           cpuABILower.startsWith("arm-5") ) {
+                    return ARMv5;
+                } else if( cpuABILower.startsWith("armv6") ||
+                           cpuABILower.startsWith("arm-v6") ||
+                           cpuABILower.startsWith("arm-6") ) {
+                    return ARMv6;
+                } else {
+                    return ARM;
+                }
+            } else if( cpuABILower.equals("sparcv9") ) {
+                return SPARCV9_64;
+            } else if( cpuABILower.equals("sparc") ) {
+                return SPARC_32;
+            } else if( cpuABILower.equals("pa_risc2.0") ) {
+                return PA_RISC2_0;
+            } else if( cpuABILower.startsWith("ppc64") ) {
+                return PPC64;
+            } else if( cpuABILower.startsWith("ppc") ) {
+                return PPC;
+            } else if( cpuABILower.startsWith("mips") ) {
+                return MIPS_32;
+            } else {
+                throw new RuntimeException("Please port CPUType detection to your platform (CPU_ABI string '" + cpuABILower + "')");
+            }
+        }
     }
 
     public enum ABIType {
-        GENERIC_ABI       ( 0x0000 ),
+        GENERIC_ABI       ( 0x00 ),
         /** ARM GNU-EABI ARMEL -mfloat-abi=softfp */
-        EABI_GNU_ARMEL    ( 0x0001 ),
+        EABI_GNU_ARMEL    ( 0x01 ),
         /** ARM GNU-EABI ARMHF -mfloat-abi=hard */
-        EABI_GNU_ARMHF    ( 0x0002 ),
+        EABI_GNU_ARMHF    ( 0x02 ),
         /** ARM EABI AARCH64 (64bit) */
-        EABI_AARCH64      ( 0x0003 );
+        EABI_AARCH64      ( 0x03 );
 
         public final int id;
 
         ABIType(final int id){
             this.id = id;
         }
+
+        /**
+         * Returns {@code true} if the given {@link ABIType} is compatible
+         * w/ this one, i.e. they are equal.
+         */
+        public final boolean isCompatible(final ABIType other) {
+            if( null == other ) {
+                return false;
+            } else {
+                return other == this;
+            }
+        }
+
+        public static final ABIType query(final CPUType cpuType, final String cpuABILower) {
+            if( null == cpuType ) {
+                throw new IllegalArgumentException("Null cpuType");
+            } else if( null == cpuABILower ) {
+                throw new IllegalArgumentException("Null cpuABILower");
+            } else if( CPUFamily.ARM == cpuType.family ) {
+                if( !cpuType.is32Bit ) {
+                    return EABI_AARCH64;
+                } else if( cpuABILower.equals("armeabi-v7a-hard") ) {
+                    return EABI_GNU_ARMHF;
+                } else {
+                    return EABI_GNU_ARMEL;
+                }
+            } else {
+                return GENERIC_ABI;
+            }
+        }
     }
 
     private static final String useTempJarCachePropName = "jogamp.gluegen.UseTempJarCache";
@@ -261,26 +350,6 @@ public class Platform extends PlatformPropsImpl {
     public static void initSingleton() { }
 
     /**
-     * Returns true only if having {@link java.nio.LongBuffer} and {@link java.nio.DoubleBuffer} available.
-     */
-    public static boolean isJavaSE() {
-        return JAVA_SE;
-    }
-
-    /**
-     * Returns true only if being compatible w/ language level 6, e.g. JRE 1.6.
-     * <p>
-     * Implies {@link #isJavaSE()}.
-     * </p>
-     * <p>
-     * <i>Note</i>: We claim Android is compatible.
-     * </p>
-     */
-    public static boolean isJava6() {
-        return JAVA_6;
-    }
-
-    /**
      * Returns true if this machine is little endian, otherwise false.
      */
     public static boolean isLittleEndian() {
@@ -328,7 +397,7 @@ public class Platform extends PlatformPropsImpl {
      * Returns the CPU family.
      */
     public static CPUFamily getCPUFamily() {
-        return CPU_ARCH.getFamily();
+        return CPU_ARCH.family;
     }
 
     /**
diff --git a/src/java/com/jogamp/common/util/VersionUtil.java b/src/java/com/jogamp/common/util/VersionUtil.java
index 6949d62..aef3fc2 100644
--- a/src/java/com/jogamp/common/util/VersionUtil.java
+++ b/src/java/com/jogamp/common/util/VersionUtil.java
@@ -58,10 +58,10 @@ public class VersionUtil {
 
         // environment
         sb.append("Platform: ").append(Platform.getOSType()).append(" / ").append(Platform.getOSName()).append(' ').append(Platform.getOSVersion()).append(" (").append(Platform.getOSVersionNumber()).append("), ");
-        sb.append(Platform.getArchName()).append(" (arch), ").append(Platform.getABIType()).append(", ");
+        sb.append(Platform.getArchName()).append(" (").append(Platform.getCPUType()).append(", ").append(Platform.getABIType()).append("), ");
         sb.append(Runtime.getRuntime().availableProcessors()).append(" cores");
         sb.append(Platform.getNewline());
-        if( AndroidVersion.isAvailable) {
+        if( Platform.OSType.ANDROID == PlatformPropsImpl.OS_TYPE ) {
             sb.append("Platform: Android Version: ").append(AndroidVersion.CODENAME).append(", ");
             sb.append(AndroidVersion.RELEASE).append(" [").append(AndroidVersion.RELEASE).append("], SDK: ").append(AndroidVersion.SDK_INT).append(", ").append(AndroidVersion.SDK_NAME);
             sb.append(Platform.getNewline());
@@ -73,8 +73,8 @@ public class VersionUtil {
         sb.append("Platform: Java Version: ").append(Platform.getJavaVersion()).append(" (").append(Platform.getJavaVersionNumber()).append("u").append(PlatformPropsImpl.JAVA_VERSION_UPDATE).append("), VM: ").append(Platform.getJavaVMName());
         sb.append(", Runtime: ").append(Platform.getJavaRuntimeName()).append(Platform.getNewline());
         sb.append("Platform: Java Vendor: ").append(Platform.getJavaVendor()).append(", ").append(Platform.getJavaVendorURL());
-        sb.append(", JavaSE: ").append(Platform.isJavaSE());
-        sb.append(", Java6: ").append(Platform.isJava6());
+        sb.append(", JavaSE: ").append(PlatformPropsImpl.JAVA_SE);
+        sb.append(", Java6: ").append(PlatformPropsImpl.JAVA_6);
         sb.append(", AWT enabled: ").append(Platform.AWT_AVAILABLE);
         sb.append(Platform.getNewline()).append(SEPERATOR);
 
diff --git a/src/java/com/jogamp/gluegen/JavaConfiguration.java b/src/java/com/jogamp/gluegen/JavaConfiguration.java
index b64c041..3924ec2 100644
--- a/src/java/com/jogamp/gluegen/JavaConfiguration.java
+++ b/src/java/com/jogamp/gluegen/JavaConfiguration.java
@@ -42,6 +42,7 @@ package com.jogamp.gluegen;
 
 import com.jogamp.gluegen.JavaEmitter.EmissionStyle;
 import com.jogamp.gluegen.JavaEmitter.MethodAccess;
+
 import java.io.*;
 import java.lang.reflect.Array;
 import java.util.*;
@@ -53,6 +54,7 @@ import com.jogamp.gluegen.cgram.types.*;
 
 import java.util.logging.Logger;
 
+import jogamp.common.os.MachineDescriptionRuntime;
 import static java.util.logging.Level.*;
 import static com.jogamp.gluegen.JavaEmitter.MethodAccess.*;
 import static com.jogamp.gluegen.JavaEmitter.EmissionStyle.*;
@@ -164,6 +166,7 @@ public class JavaConfiguration {
     private final Map<String, String> structPackages = new HashMap<String, String>();
     private final List<String> customCCode = new ArrayList<String>();
     private final List<String> forcedStructs = new ArrayList<String>();
+    private final Map<String, String> structMachineDescriptorIndex = new HashMap<String, String>();
     private final Map<String, String> returnValueCapacities = new HashMap<String, String>();
     private final Map<String, String> returnValueLengths = new HashMap<String, String>();
     private final Map<String, List<String>> temporaryCVariableDeclarations = new HashMap<String, List<String>>();
@@ -547,7 +550,12 @@ public class JavaConfiguration {
   }
 
   /** Returns true if the glue code for the given function will be
-      manually implemented by the end user. */
+      manually implemented by the end user.
+   * <p>
+   * If symbol references a struct field or method, see {@link #canonicalStructFieldSymbol(String, String)},
+   * it describes field's array-length or element-count referenced by a pointer.
+   * </p>
+   */
   public boolean manuallyImplement(final String functionName) {
     return manuallyImplement.contains(functionName);
   }
@@ -637,6 +645,20 @@ public class JavaConfiguration {
   }
 
   /**
+   * Returns a MessageFormat string of the Java code defining {@code mdIdx},
+   * i.e. the index of the static MachineDescriptor index for structs.
+   * <p>
+   * If undefined, code generation uses the default expression:
+   * <pre>
+   *     private static final int mdIdx = MachineDescriptionRuntime.getStatic().ordinal();
+   * </pre>
+   * </p>
+   */
+  public String returnStructMachineDescriptorIndex(final String structName) {
+    return structMachineDescriptorIndex.get(structName);
+  }
+
+  /**
    * Returns a MessageFormat string of the C expression calculating
    * the capacity of the java.nio.ByteBuffer being returned from a
    * native method, or null if no expression has been specified.
@@ -1101,6 +1123,10 @@ public class JavaConfiguration {
       readTemporaryCVariableAssignment(tok, filename, lineNo);
       // Warning: make sure delimiters are reset at the top of this loop
       // because TemporaryCVariableAssignment changes them.
+    } else if (cmd.equalsIgnoreCase("StructMachineDescriptorIndex")) {
+      readStructMachineDescriptorIndex(tok, filename, lineNo);
+      // Warning: make sure delimiters are reset at the top of this loop
+      // because StructMachineDescriptorIndex changes them.
     } else if (cmd.equalsIgnoreCase("ReturnValueCapacity")) {
       readReturnValueCapacity(tok, filename, lineNo);
       // Warning: make sure delimiters are reset at the top of this loop
@@ -1499,6 +1525,18 @@ public class JavaConfiguration {
     }
   }
 
+  protected void readStructMachineDescriptorIndex(final StringTokenizer tok, final String filename, final int lineNo) {
+    try {
+      final String structName = tok.nextToken();
+      String restOfLine = tok.nextToken("\n\r\f");
+      restOfLine = restOfLine.trim();
+      structMachineDescriptorIndex.put(structName, restOfLine);
+    } catch (final NoSuchElementException e) {
+      throw new RuntimeException("Error parsing \"StructMachineDescriptorIndex\" command at line " + lineNo +
+        " in file \"" + filename + "\"", e);
+    }
+  }
+
   protected void readReturnValueCapacity(final StringTokenizer tok, final String filename, final int lineNo) {
     try {
       final String functionName = tok.nextToken();
diff --git a/src/java/com/jogamp/gluegen/JavaEmitter.java b/src/java/com/jogamp/gluegen/JavaEmitter.java
index 7e5ce51..48c7047 100644
--- a/src/java/com/jogamp/gluegen/JavaEmitter.java
+++ b/src/java/com/jogamp/gluegen/JavaEmitter.java
@@ -963,7 +963,10 @@ public class JavaEmitter implements GlueEmitter {
     javaWriter.println();
     javaWriter.println("  StructAccessor accessor;");
     javaWriter.println();
-    javaWriter.println("  private static final int mdIdx = MachineDescriptionRuntime.getStatic().ordinal();");
+    final String cfgMachDescrIdxCode = cfg.returnStructMachineDescriptorIndex(containingJTypeName);
+    final String machDescrIdxCode = null != cfgMachDescrIdxCode ? cfgMachDescrIdxCode : "private static final int mdIdx = MachineDescriptionRuntime.getStatic().ordinal();";
+    javaWriter.println("  "+machDescrIdxCode);
+    javaWriter.println("  private final MachineDescription md;");
     javaWriter.println();
     // generate all offset and size arrays
     generateOffsetAndSizeArrays(javaWriter, "  ", containingJTypeName, structCType, null, null); /* w/o offset */
@@ -1037,22 +1040,29 @@ public class JavaEmitter implements GlueEmitter {
       }
     }
     javaWriter.println();
-    javaWriter.println("  public static int size() {");
-    javaWriter.println("    return "+containingJTypeName+"_size[mdIdx];");
-    javaWriter.println("  }");
-    javaWriter.println();
-    javaWriter.println("  public static " + containingJTypeName + " create() {");
-    javaWriter.println("    return create(Buffers.newDirectByteBuffer(size()));");
-    javaWriter.println("  }");
-    javaWriter.println();
-    javaWriter.println("  public static " + containingJTypeName + " create(java.nio.ByteBuffer buf) {");
-    javaWriter.println("      return new " + containingJTypeName + "(buf);");
-    javaWriter.println("  }");
-    javaWriter.println();
-    javaWriter.println("  " + containingJTypeName + "(java.nio.ByteBuffer buf) {");
-    javaWriter.println("    accessor = new StructAccessor(buf);");
-    javaWriter.println("  }");
-    javaWriter.println();
+    if( !cfg.manuallyImplement(JavaConfiguration.canonicalStructFieldSymbol(containingJTypeName, "size")) ) {
+        javaWriter.println("  public static int size() {");
+        javaWriter.println("    return "+containingJTypeName+"_size[mdIdx];");
+        javaWriter.println("  }");
+        javaWriter.println();
+    }
+    if( !cfg.manuallyImplement(JavaConfiguration.canonicalStructFieldSymbol(containingJTypeName, "create")) ) {
+        javaWriter.println("  public static " + containingJTypeName + " create() {");
+        javaWriter.println("    return create(Buffers.newDirectByteBuffer(size()));");
+        javaWriter.println("  }");
+        javaWriter.println();
+        javaWriter.println("  public static " + containingJTypeName + " create(java.nio.ByteBuffer buf) {");
+        javaWriter.println("      return new " + containingJTypeName + "(buf);");
+        javaWriter.println("  }");
+        javaWriter.println();
+    }
+    if( !cfg.manuallyImplement(JavaConfiguration.canonicalStructFieldSymbol(containingJTypeName, containingJTypeName)) ) {
+        javaWriter.println("  " + containingJTypeName + "(java.nio.ByteBuffer buf) {");
+        javaWriter.println("    md = MachineDescription.StaticConfig.values()[mdIdx].md;");
+        javaWriter.println("    accessor = new StructAccessor(buf);");
+        javaWriter.println("  }");
+        javaWriter.println();
+    }
     javaWriter.println("  public java.nio.ByteBuffer getBuffer() {");
     javaWriter.println("    return accessor.getBuffer();");
     javaWriter.println("  }");
@@ -1129,7 +1139,7 @@ public class JavaEmitter implements GlueEmitter {
                 if( fieldTypeNativeSizeFixed ) {
                     javaWriter.println("    accessor.set" + capJavaTypeName + "At(" + fieldName+"_offset[mdIdx], val);");
                 } else {
-                    javaWriter.println("    accessor.set" + capJavaTypeName + "At(" + fieldName+"_offset[mdIdx], val, MachineDescriptionRuntime.getStatic().md."+sizeDenominator+"SizeInBytes());");
+                    javaWriter.println("    accessor.set" + capJavaTypeName + "At(" + fieldName+"_offset[mdIdx], val, md."+sizeDenominator+"SizeInBytes());");
                 }
                 javaWriter.println("    return this;");
                 javaWriter.println("  }");
@@ -1143,7 +1153,7 @@ public class JavaEmitter implements GlueEmitter {
             if( fieldTypeNativeSizeFixed ) {
                 javaWriter.println("accessor.get" + capJavaTypeName + "At(" + fieldName+"_offset[mdIdx]);");
             } else {
-                javaWriter.println("accessor.get" + capJavaTypeName + "At(" + fieldName+"_offset[mdIdx], MachineDescriptionRuntime.getStatic().md."+sizeDenominator+"SizeInBytes());");
+                javaWriter.println("accessor.get" + capJavaTypeName + "At(" + fieldName+"_offset[mdIdx], md."+sizeDenominator+"SizeInBytes());");
             }
             javaWriter.println("  }");
           } else {
@@ -1240,7 +1250,9 @@ public class JavaEmitter implements GlueEmitter {
       writer.print(")");
   }
 
-  private void generateOffsetAndSizeArrays(final PrintWriter writer, final String prefix, final String fieldName, final Type fieldType, final Field field, final String postfix) {
+  private void generateOffsetAndSizeArrays(final PrintWriter writer, final String prefix,
+                                           final String fieldName, final Type fieldType,
+                                           final Field field, final String postfix) {
       if(null != field) {
           writer.print(prefix+"private static final int[] "+fieldName+"_offset = new int[] { ");
           for( int i=0; i < machDescTargetConfigs.length; i++ ) {
@@ -1668,7 +1680,7 @@ public class JavaEmitter implements GlueEmitter {
                       if( baseCElemNativeSizeFixed ) {
                           javaWriter.println("    accessor.set" + baseJElemTypeNameC + "At(" + fieldName+"_offset[mdIdx], val);");
                       } else {
-                          javaWriter.println("    accessor.set" + baseJElemTypeNameC + "At(" + fieldName+"_offset[mdIdx], val, MachineDescriptionRuntime.getStatic().md."+baseCElemSizeDenominator+"SizeInBytes());");
+                          javaWriter.println("    accessor.set" + baseJElemTypeNameC + "At(" + fieldName+"_offset[mdIdx], val, md."+baseCElemSizeDenominator+"SizeInBytes());");
                       }
                       javaWriter.println("    return this;");
                       javaWriter.println("  }");
@@ -1831,7 +1843,7 @@ public class JavaEmitter implements GlueEmitter {
                   if( baseCElemNativeSizeFixed ) {
                       javaWriter.println("    return accessor.get" + baseJElemTypeNameC + "At(" + fieldName+"_offset[mdIdx]);");
                   } else {
-                      javaWriter.println("    return accessor.get" + baseJElemTypeNameC + "At(" + fieldName+"_offset[mdIdx], MachineDescriptionRuntime.getStatic().md."+baseCElemSizeDenominator+"SizeInBytes());");
+                      javaWriter.println("    return accessor.get" + baseJElemTypeNameC + "At(" + fieldName+"_offset[mdIdx], md."+baseCElemSizeDenominator+"SizeInBytes());");
                   }
                   javaWriter.println("  }");
                   javaWriter.println();